The overall objective of this TTURC is to improve our understanding how national level tobacco control policies can be applied to reduce the harms caused by tobacco. _itae recently adopted Framework Convention on Tobacco Control (FCTC), the first international treaty devoted to a health issue, has recently placed national-level tobacco control policies in the spotlight. Governments are now paying considerable attention to which national-level policy or combination of policies work best to deter tobacco use. The goal of this TTURC is to expand the science base for policy approaches for controlling tobacco by fostering transdisciptinary research that can lead to: 1. rigorous evaluation of the psychosocial and behavioral eft_cts ofnationaMevel tobacco control policies in multiple developed and developing countries 2. a more fully developed and empirically based understanding of how and why national level tobacco control policies influence tobacco related behaviors, that is, the psychosocial mechanisms for policy effects, with particular interest in how those effects might vary across countries that vary in economic level and culture; 3. new methods and analytic approaches for the evaluation of tobacco control policies; 4. an expanded global network of scientists to conduct and contribute to research on tobacco control policies; and 5. dissemination of research findings to inform the development and adoption of future national-level policy initiatives.